The pathogenesis of Gram-negative septic shock, a leading cause of mortality in critically ill patients, is a consequence of the overwhelming innate immune response to endotoxins, or lipopolysaccharides (LPS), present on the surface of Gram-negative bacteria (including Category A and B Select Agents). We have shown that relatively simple and synthetically easily accessible molecules of the lipopolyamine class specifically bind to the toxic Lipid A moiety of LPS and neutralize its toxicity. Extensive structure-activity relationship studies on lipopolyamines using a combination of classical medicinal chemistry approaches, combinatorial lead generation, molecular modeling, high-throughput screening, and the development of novel secondary and tertiary-level assays to verify the premise of true sequestration of LPS by these compounds in vitro as well as in animal models have led to the identification of DS-96, an N- alkylhomospermine derivative. The in vitro and in vivo LPS-sequestering and -neutralizing properties of DS- 96 rival that of polymyxin B, a gold standard LPS sequestrant in every respect thus far. Importantly, in all of our in vivo studies to date, we have been unable to detect any apparent toxicity for DS-96. We propose to further the preclinical development of DS-96, establish efficacy in alternate animal models of endotoxic shock, characterize its safety profile, and obtain detailed pharmacokinetic and ADME data.